That must be tough for you both. Is he exercising, eating well, having a good sleep routine and doing things he (used to) enjoys? Simple CBT can really help the depression to pass quicker. If nothing helps then maybe his meds need to be tweaked so he should see his doctor soon. Also, when I was on Cymbalta (SNRI anti-depressant) it took over a month to work so maybe there is hope on the horizon.